Lock.



E. KURSTEINER.

LOCK.

APPLICATION FILED NOV. 22, 1915.

1 ,1 92,434, Patented July 25, 1916.

ERNST KIIRSTEINER, OF GHRISTIANIA, NORWAY.

LOCK.

Specification of Letters Patent.

Patented July 25, 1916.

Application filed November 22, 1915. Serial No. 62,785.

To all whom it may concern:

Be it known that I, ERNST Kt'IRsTErNnR, a citizen of the Republic of Switzerland, residing at Ohristiania, Norway, have invented certain new and useful Improvements in Locks; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being bad to the accompanying drawings, and to letters or figures of reference marked thereon, which form a part of this specification.

The present invention relates to looks and more particularly to snap locks of the tumbler lock type (cylinder locks, etc.) The ordinary locks of this kind present the, disadvantage that they may be opened from outside by means of a steel-blade or the like in sorted through the narrow slot between door and jamb, and acting upon the inclined surface of the latch bolt.

One object of the present invention is to provide a lock which can not be opened in this way, and I attain this object by means of a projecting rib in front of and integral with the keeper so that a groove is formed between said rib and the front surface of the keeper, a projection on the lock caseifitting into said groove when the lock is in operative position.

Another object of the invention is to provide means in a lock of this kind to prevent the door from being opened by means of the knob from inside. If for instance a flat is left unoccupied for some time a burglar may gain entrance by breaking the glass and get at the knob with his hand even if the door window is not large enough to admit a person. According to the present invention this is avoided by means of a sliding bar one end of which cooperates with the knob to lock the same while the other end has a hook or projection adapted to fall in line with the rib on the lock case when the knob is locked in its position. Then when the lock is in operative position the said sliding bar is in turn locked by its aforesaid projection falling into the groove of the keeper, and in this position the lock can only be operated by key.

Other features of the invention will appear from the following description of an embodiment of the same.

On the drawings: Figure 1 is a longitudinal section of a tumbler snap lock according to the invention. Fig. 2 is an inside view of the lock.

1 is the keeper which is provided with a projecting rib 2, a groove3 being formed between said rib and the front face of the keeper.

4 is a rib on the lock case 5 which is adapted to fit into the groove 3 as seen on the drawing. In this way the latch bolt 17 is prevented from being slid back by means of a blade or the like inserted through the door slot and further the lock case is fastened to the keeper in such a way that it can not be moved endwise away from the same as is the case with other locks.

In order to prevent the door from being opened by turning the knob, a. sliding bar 7 inside the lock-case has a lug 8on one end adapted to engage a notch 11 in the knob disk 10. The other end of the sliding bar has a hook or lug 12 adapted to take into the groove 3 of the keeper in line with the rib 4 when the door is closed. A knob 9 serves to move the bar 7, while the door is open, into operative position as shown in full or into inoperative position, shown in dotted lines.

The rib 2 has its operating surface perpendicular to the plane of movement of the latch-bolt 17 so that only one such rib is needed to prevent the two parts of the lock from being separated.

When the sliding bar 7 is in the locking position the hand-knob 6 of the lock can not be moved and the lock may be opened by key only. In order however to still enable the lock to be opened from inside an auxiliary tumbler lock (14, 15) is provided in the knob 6 the cylinder 15 of which is independent of the hand knob and carries on its inner end an arm 16 acting on the cross-plate 19 of the latch-bolt 17. The latter therefore may be opened by means of a latch key 13 inserted in the tumbler-lock 14, 15 (the details of which is not shown on the drawing).

Although it is preferred to arrange the auxiliary look inside the knob 6 this is by no means necessary, and the said lockmay be located at any other convenient place on the inside on the sole condition that it is able to 105 actuate the latch bolt independently of the knob 6.

Claims.

1. A snap lock comprising a keeper, a lock case, a knob, a latch bolt adapted to be retracted from the indoor side by means of the knob, a projecting rib in front of the keeper, a groove between the keeper face and said rib, and means in the lock case for preventing the operation of the knob and adapted to be locked in turn by means of the said 5 groove and rib on the keeper.

2. A snap lock comprising a keeper, a lock case, a knob, a latch bolt adapted to be retracted from the indoor side by means of the knob, a projecting rib in front of the keeper, a groove between the keeper face and said rib, and a sliding bar in the lock case co operating in one position with the knob so as to prevent the movement of the same and being locked in the same position by meansof the rib and groove on the keeper.

3. A snap lock comprising a keeper, a lock case, a knob, a latch bolt adapted to be retracted from the indoor side by means of the a knob, a projecting rib in front of the keeper, a groove between the keeper and rib, means in the lock case for preventing the 0peration of the knob and adapted to bevlocked in turn by means of the said groove and rib on the keeper, and means independent of the knob for actuating the latch bolt from inside.

4. A snap lock comprising a keeper, a lock tracted from the indoor side by means of the knob, a projecting rib in front of the keeper, a groove between the keeper and rib, means in the lock case for preventing the operation of the knob and adapted to be locked in turn by means of the groove-and rib on the keeper, and an auxiliary lock on the inside of the lock case for actuating the latch bolt independent of the knob.

5. A snap lock comprising, a keeper, a look case, a knob, a latch bolt adapted to be retracted from the indoor side by means of the knob, a projecting rib in front of the keeper, a groove between the keeper and rib, means in the lock case for preventing the operation of the knob and adapted to be locked in turn by means of the groove and rib on the keeper, and an auxiliary lock inside the knob but independent from the same fog actuating the latch bolt from the indoor s1 e.

In testimony that I claim the foregoing as my invention, I have signed my name in presence of two subscribing witnesses.

ERNST KURSTEINER.

Witnesses:

M. E. GULBERNsEN, THs. BERG.

Gopies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C. 

